The past several years have seen an explosive growth of the internet, and specifically, in the growth of the World Wide Web (hereafter "the Web"). The Web is built around a network of "server" computers which exchange requests and data from each other using the hypertext transfer protocol ("http"). A human designer designs the layout of a Web page and specifies the layout of the page using HTML ("Hypertext Markup Language"). Several versions of HTML are currently in existence. Examples include HTML versions 2.0 and 3.0, as specified by the WWW Consortium of MIT.
A user views a Web page using one of a number of commercially available "browser" programs. The browser submits an appropriate http request to establish a communications link with a Web server of the network. A typical http request references a Web page by its unique Uniform Resource Locator ("URL"). A URL identifies the Web server hosting that Web page, so that an http request for access to the Web page can be routed to the appropriate Web server for handling. Web pages can also be linked graphically to each other.
Ever since the Mosaic browser, which was developed by the University of Illinois, it has been possible to have a sound effect as the destination for a hypertext link on the Web. When the user clicks on the area associated with the sound, the browser retrieves an audio file from the remote server and plays it. Early browsers actually played audio files by passing them to so-called "helper applications," but current browsers have audio players built in. Unfortunately, this standard approach (retrieving the audio file at a user's request) is ill-suited for small sound effects (e.g., a bird call or a name pronunciation) because of network latency. The user does not get to hear the sound until several seconds after he or she has clicked on the link. Experimentation has shown that a user needs to get the result of traversing a hypertext link within a single second for the user to feel that he or she is navigating freely.
A second approach supports so-called "background sounds" that will play automatically as soon as the browser has finished downloading a page. The problem with this approach is that the sound will be played under all circumstances, and thus not under user control when the user desires to hear a specific sound. Also, no more than a single sound can be associated with the page.